LIGHT-CONTROLLED ANCHORING OF MEANDERING SPIRAL WAVES

Meandering spiral waves in the light-sensitive excitable Belousov-Zhabotinsky reaction with tips proceeding along epicycles were forced to rigid rotation. This spiral anchoring was induced by an argon laser beam creating an unexcitable disk close to the tip. The stabilized spirals rotate with frequencies above the low secondary frequency of meandering. Simulations using a simple reaction-diffusion model demonstrate that anchoring is only possible up to a critical radius of the disk. For this critical value anchored spirals obey the unstable primary parameters (radius and frequency) of compound motion.